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LED lighting badly suppresses human melatonin production at night

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Re: LED lighting badly suppresses human melatonin production at night

#191

Post by otikik »

jahsome wrote: post #21
karmaMeansCool wrote: post #15

There are also probably very personal and biological variables involved too that the post doesn't mention. I stare into monitors and phones all day long. Every light in the house is full-blown LED. I can't help but fall asleep at 20:00 in an led lit room watching led TVs, while my led phone drops onto the floor after I've fallen asleep. I've been in an extreme LED environment for over a decade and never have problems…

I've battled the opposite in the form of clinical, anxiety-driven insomnia my whole life. I've found it utterly debilitating at times and have quite literally struggled since birth, long before electronics and LEDs were common. I can confidently say you're so right about the number (and type) of variables. Sleep hygiene as we say in the biz is a very complex and personal issue. I've tried everything under the sun fro…

How is your breathing while sleeping? If you have sleep apnea you could have subconsciously associated sleeping with axfixiation.

This is the particular problem I have. A CPAP machine remedied the breathing, but it was very uncomfortable to wear, waking me up. Now I use nose strips (Breathe right) and a slightly inclined bed. I still snore but it seems to have improved my breathing. Next on the list: losing weight.

Re: LED lighting badly suppresses human melatonin production at night

#192

Post by regularfry »

marcell wrote: post #143
sacnoradhq wrote: post #122

Earlier quoted context omitted.

Artificial lighting has existed for hundreds, if not tens of thousands, of years. People used to breathe superfines and ultrafines from daily cooking fires in nearly indoor conditions. Hell, people living in cities next to highways have no idea how they're shortening their lives if they don't have extreme MERV air filtration like I do. The AQI inside right now hovers at ~5. Outside, it varies from 15 to 200. I've bee…

> is unscientific, lacking in perspective, and offensive. I agree it is unscientific speculation. Science doesn’t have any answers. As one example, there are no conclusive scientific answers on why global male testosterone is declining, or why American girls are experiencing early puberty. Any plausible explanation has compelling reasons to dismiss it, and we can’t know scientifically if they are correct. Yet we can…

> Yet we can see both clearly in the data. If you want to escape these changes, you can only get answers outside of scientific knowledge.

Those would be not answers, then.

Re: LED lighting badly suppresses human melatonin production at night

#193

Post by ilaksh »

jahsome wrote: post #21
karmaMeansCool wrote: post #15

There are also probably very personal and biological variables involved too that the post doesn't mention. I stare into monitors and phones all day long. Every light in the house is full-blown LED. I can't help but fall asleep at 20:00 in an led lit room watching led TVs, while my led phone drops onto the floor after I've fallen asleep. I've been in an extreme LED environment for over a decade and never have problems…

I've battled the opposite in the form of clinical, anxiety-driven insomnia my whole life. I've found it utterly debilitating at times and have quite literally struggled since birth, long before electronics and LEDs were common. I can confidently say you're so right about the number (and type) of variables. Sleep hygiene as we say in the biz is a very complex and personal issue. I've tried everything under the sun fro…

OK not to be that guy.. and please don't misunderstand, I assume that like you say you are just different and that individual variability plays a part and people can have sleep conditions.

But since you did not literally mention either thing, how much sun exposure do you get per day? And how much Vitamin D3 do you take during the day, and melatonin at night?

Re: LED lighting badly suppresses human melatonin production at night

#194

Post by ricksunny »

I find that nighttime alertness is artificially (and undesirably) propped up by having the sum total of the world's knowledge at my fingertips. The LED brightness exacerbates. I haven't RCT'd tbis, but my best guess is that excessive nighttime alertness is 2/3 due to content availability, 1/3 screen (and perhaps ambient) brightness. I take active steps to have both passively cut off after a certain time.

Re: LED lighting badly suppresses human melatonin production at night

#195

Post by londons_explore »

greggsy wrote: post #189
londons_explore wrote: post #185

Earlier quoted context omitted.

I am disappointed that many phones/tablets don't go very dim. From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting. I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithm…

It’s possible to set a custom filter in iOS, which reduces the brightness even further, but only in one colour, ie red. Better than nothing. The main issue i think is that backlights tend to flicker at low brightness.

They do... But thats down to poor design decisions.

Human vision extends from about 10^5 cd/m^2 to 10^-5 cd/m^2 [1].

Typical backlights use something like PWM to modulate the brightness. That means you need to be able to scale your backlight by a factor of 10^10 to cover the whole human vision range. And if your CPU runs at 1 Ghz (10^9), then at the dimmest setting then even being on for a single clock cycle would be a flash every 10 seconds - clearly unacceptable, and even then, few backlight controllers could handle a 1 nanosecond pulse!

The fix is to use PWM combined with settable 'modes'. The modes could be 'bright light' (using all the backlight LED's, perhaps a few watts total), and a dim light mode, which uses just one LED through a high value resistor, of just a few tens of microwatts. Your two modes have a factor of 10^5 between them in brightness. So now the PWM on your CPU only needs a resolution of 10^5, which it can do.

[1]: https://www.researchgate.net/figure/Approximate-luminance-ra...

Re: LED lighting badly suppresses human melatonin production at night

#196

Post by oblio »

londons_explore wrote: post #185
koverda wrote: post #107

Regarding the quoted e-book study: > Third, in the present study, the LE-eBook was set to maximum brightness throughout the 4-h reading session, whereas, by comparison, the print-book condition consisted of reflected exposure to very dim light. Yeah, max brightness is probably going to make an impact. I bet if you were in a room with a bright light reading a book, with an equivalent amount of lumens going into your e…

I am disappointed that many phones/tablets don't go very dim. From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting. I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithm…

Most Android devices have an "extra dim" option hidden somewhere in the buttons at the top (you might have to add it yourself from the extra buttons).

Samsung: https://www.samsung.com/au/support/mobile-devices/activate-e...

It's really dim, one time in the morning I thought the phone screen was off and it was just set to extra dim :-))

Re: LED lighting badly suppresses human melatonin production at night

#197

Post by harvey9 »

vidarh wrote: post #154
textbookrental wrote: post #86

Earlier quoted context omitted.

I've been a terrible sleeper for about a decade. Weeks on end where I am only sleeping a few hours a night. Can't fall asleep, can't stay asleep, just tired all the time. Tried all the sleep hygiene recommendations but made no difference. Started supplementing with creatine and about a month later had the best sleep of my adult life. Shortly after switching creatine brands, I noticed my restless legs were back and I…

I'd worry about what else is in the one that helps you sleep to cause there to be a difference.

Or perhaps there is something lacking in the brand that does not help them sleep? By that I mean maybe there is less creatine than claimed, or it is supplied in a form that is harder to digest.

Re: LED lighting badly suppresses human melatonin production at night

#198

Post by mike_h »

greggsy wrote: post #189
londons_explore wrote: post #185

Earlier quoted context omitted.

I am disappointed that many phones/tablets don't go very dim. From flagship to cheap, it seems that if you're in a pitch black room and check the time on your phone, the light will illuminate the whole room, even on the dimmest setting. I actually modded my phone by putting a resistor in the LED backlight circuit, which divided the brightness by 1000 - and it was still plenty bright at night (human eyes are logarithm…

It’s possible to set a custom filter in iOS, which reduces the brightness even further, but only in one colour, ie red. Better than nothing. The main issue i think is that backlights tend to flicker at low brightness.

There’s a full-color dimming filter in Accessibility -> Zoom -> Zoom Filter -> Low Light. You can assign it to the accessibility shortcut for quick access.

Re: LED lighting badly suppresses human melatonin production at night

#199

Post by oblio »

treeman79 wrote: post #116
marcell wrote: post #79

There is always a time lag between the introduction of a cool new technology, and the discovery of its negative effects on human health. DDT was invented in the 1940's, and it wasn't until twenty years later that people discovered its negative effects through bioaccumulation. Teflon was invented in the 1930's, and it again took decades to discover its negative effects on human health, apparently under high heat. Ciga…

Banning ddt has lead to the death of many millions of people

How?

Re: LED lighting badly suppresses human melatonin production at night

#200

Post by vidarh »

harvey9 wrote: post #197
vidarh wrote: post #154

Earlier quoted context omitted.

I'd worry about what else is in the one that helps you sleep to cause there to be a difference.

Or perhaps there is something lacking in the brand that does not help them sleep? By that I mean maybe there is less creatine than claimed, or it is supplied in a form that is harder to digest.

That is of course also an option, but a less scary one
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